Davon is picking out some movies to rent, and he has narrowed down his selections to 4 children's movies, 3 documentaries, 6 comedies, and 5 mysteries. How many different combinations of 9 movies can he rent if he wants all 6 comedies?

220

Step-by-step explanation:

There are 6 comedies and 12 non-comedies.  He wants all 6 of the comedies, and 3 of the non-comedies.

The number of ways he can choose 6 comedies from 6 is ₆C₆ = 1.

The number of ways he can choose 3 non-comedies from 12 is ₁₂C₃ = 220.

So the total number of combinations is 1 × 220 = 220.

29.5977692753

step-by-step explanation:

δabc ≅ δdcb by sas because

db ≅ ac . . given (side)

bc ≅ bc . . reflexive property (side)

∠dbc ≅ ∠ acb . . alternate interior angles where transversal bc crosses parallel lines bd and ac (included angle)